2.9*0.45+0.29*4.2+0.029*13怎样用简便方法

问题描述:

2.9*0.45+0.29*4.2+0.029*13怎样用简便方法

2.9*0.45+0.29*4.2+0.029*13
=2.9*0.45+2.9*0.42+2.9*0.13
=2.9*(0.45+0.42+0.13)
=2.9*1
=2.9